Whilst the default SLUB allocator happily just merges the original
allocation flags from kmem_cache_create() with those passed through
kmem_cache_alloc(), there is a code path in the SLAB allocator which
will aggressively BUG_ON() if the cache was created with SLAB_CACHE_DMA
but GFP_DMA is not specified for an allocation:
kernel BUG at mm/slab.c:2536!
Internal error: Oops - BUG: 0 [#1] SMP ARM
Modules linked in:[ 1.299311] Modules linked in:
CPU: 1 PID: 1 Comm: swapper/0 Not tainted
4.5.0-rc6-koelsch-05892-ge7e45ad53ab6795e #2270
Hardware name: Generic R8A7791 (Flattened Device Tree)
task: ef422040 ti: ef442000 task.ti: ef442000
PC is at cache_alloc_refill+0x2a0/0x530
LR is at _raw_spin_unlock+0x8/0xc
...
[<c02c6928>] (cache_alloc_refill) from [<c02c6630>] (kmem_cache_alloc+0x7c/0xd4)
[<c02c6630>] (kmem_cache_alloc) from [<c04444bc>]
(__arm_v7s_alloc_table+0x5c/0x278)
[<c04444bc>] (__arm_v7s_alloc_table) from [<c0444e1c>]
(__arm_v7s_map.constprop.6+0x68/0x25c)
[<c0444e1c>] (__arm_v7s_map.constprop.6) from [<c0445044>]
(arm_v7s_map+0x34/0xa4)
[<c0445044>] (arm_v7s_map) from [<c0c18ee4>] (arm_v7s_do_selftests+0x140/0x418)
[<c0c18ee4>] (arm_v7s_do_selftests) from [<c0201760>]
(do_one_initcall+0x100/0x1b4)
[<c0201760>] (do_one_initcall) from [<c0c00d4c>]
(kernel_init_freeable+0x120/0x1e8)
[<c0c00d4c>] (kernel_init_freeable) from [<c067a364>] (kernel_init+0x8/0xec)
[<c067a364>] (kernel_init) from [<c0206b68>] (ret_from_fork+0x14/0x2c)
Code: 1a000003 e7f001f2 e3130001 0a000000 (e7f001f2)
---[ end trace 190f6f6b84352efd ]---
Keep the peace by adding GFP_DMA when allocating a table.
Reported-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Tested-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
As the number of io-pgtable implementations grows beyond 1, it's time
to rationalise the quirks mechanism before things have a chance to
start getting really ugly and out-of-hand.
To that end:
- Indicate exactly which quirks each format can/does support.
- Fail creating a table if a caller wants unsupported quirks.
- Properly document where each quirk applies and why.
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Add some simple wrappers to avoid having the guts of the TLB operations
spilled all over the page table implementations, and to provide a point
to implement extra common functionality.
Acked-by: Will Deacon <will.deacon@arm.com>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Add a nearly-complete ARMv7 short descriptor implementation, omitting
only a few legacy and CPU-centric aspects which shouldn't be necessary
for IOMMU API use anyway.
Reviewed-by: Yong Wu <yong.wu@mediatek.com>
Tested-by: Yong Wu <yong.wu@mediatek.com>
Signed-off-by: Yong Wu <yong.wu@mediatek.com>
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
